Phreakish

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About Phreakish

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  1. I've been playing with an idea. I have a foldable rotor on my craft which I'm using in lieu of a parachute. With almost full tanks, I'm down to about 37 m/s on descent. It's tricky though, I have to spool up the rotor (which is on an unpowered servo as a bearing) by angling my control surfaces ~20 deg, once I reach near the rpm limits, I reduce the angle of the surfaces to ~2 deg. I don't lose much if any RPM and the craft decelerates well. If I don't spool up the rotor enough, it'll drop all revs as soon as I drop the degrees... So I'm sure it's mostly a bug thing, but I'm still having fun with it. The space-x style legs are just connected to hinges, locking is my friend here, otherwise they lack the ability to hold up the ship. The four control surfaces sticking out behind the capsule are foldable fins for control during descent. It's tricky to manage, and I've yet to really stick a landing. I'll try again later with the tanks more empty to see if I can slow it even further for a decent touchdown.
  2. and also the distinction about camber vs angle of attack. I actually don't know which side this comes down on (and you can annotate that for me), but it does give me the opportunity to elucidate my "in some flight regimes" qualification. Passengers today spend the great majority of their time airborne at cruise altitude/speed in a regime optimized for very low angle of attack. At that speed, lots of lift can be produced but little (comparatively) is needed. (The article I cited in the other thread was criticized for being wrong in one point but it made the point quite well that a small pressure differential over a large wing area can easily generate the required lift for level flight at high speed.) At the same time, drag at high speed is a killer and the design effort needs to absolutely minimize it, which means eliminate turbulence and minimize any net deflection of the air. In this regime, if Bernoulli's effect actually exists at all, it may be that it is completely sufficient in and of itself to provide the required lift. Reynolds number relates to the viscosity of a fluid flow, and increases with scale and speed (high Re means low viscosity). Kutta/Joukowski is good for approximating things at very high speeds and of very large size (think airliners instead of paper airplanes). Boundary layers are thicker where fluid flow is slower, and thinner where it is faster - Kutta allows a simpler means of determine a 'true' performance analysis of an airfoil by helping approximate an effective shape of a given foil (assuming the analysis parameters hold to all of Kutta's constraints) such that it can be analyzed using inviscid principles. In a nutshell, Kutta/Joukowski is typically used for very niche applications such as cruise regimes of large craft. It is based, however, on the very root principles of the physics of flight which can help illustrate the concepts of aerodynamic lift. One consequence of lift is drag. Induced drag is the component of drag which increases linearly with lift, and the square of velocity. Lift can be determined using Coefficient of lift and velocity, using the lift equation: L=A*Cl*q, where A is the wing area, Cl is the coefficient of lift, and q is dynamic pressure (1/2 *density*velocity-squared). Induced drag can be calculated using the equation: Cdi = (Cl^2) / (pi * AR * e) where Cl is coefficient of lift, pi is... pi (3.1415926....), AR is the aspect ratio and e is an efficiency factor. Now, I'm pretty sure KSP doesn't calculate AR or e, but maybe it has an assumed e and does calculate AR? AR is a ratio of span versus area - longer spans have a higher AR and better efficiency too. This is why airliners and gliders have very long wings. At any rate, from these equations we can see that an increase in wing area will increase lift without increasing the drag except by the amount of inherent parasitic drag the wing member creates. Parasitic drag is usually orders of magnitude lower than induced drag. The more wing area a craft has, the less angle of attack it needs, and as a result the Cl can remain low. A low Cl means low induced drag. From what I've observed, KSP doesn't technically calculate induced drag, but drag definitely increases with angle-of attack. What I've found with craft in KSP that have a hard time reaching high speed is that they either: A) lack enough wing wing area to remain aloft in the subsonic range without a significant angle-of-attack and thus create more drag that prevents more speed, B) have a high parts with lots of drag cubes that keeps total drag too high to achieve supersonic performance. Remember that any angle of attack, positive or negative, means the entire fuselage is also exposed to the relative wind (airflow around the craft) which means that the various fuselage parts being to make their own drag. By keeping the angle of attack, of both the wings and fuselage, as low as possible - drag is minimized. As a result, short fuselages with minimal wing tend to do best. Think F22 instead of SR71. Long fuselages can contribute lots of drag unless the wing area and incidence angle (rotation of wing relative the body) are tweaked just-so.
  3. The debate 'between' bernoulli and newton with respect to aviation is not a debate. It's a conflict between people of varying degree of knowledge and scientific credentials. Wings, propellers, rotors, or anything which moves through a fluid can have it's behavior and performance predicted by physics. The term "bernoulli" gets thrown around, but all Bernoulli taught is that pressure drops linearly with an increase in velocity. That knowledge can be combined with the unwaveringly true 3rd law, which states that momentum must be conserved. A flat plate makes lift the same way an airfoil does - when you tilt a flat plate, the stagnation point changes which acts on the fluid (usually air) in such a way as to cause a pressure drop above the surface. This pressure drop is responsible for the creation of the lifting force. It is also responsible for an increase in drag - usually called induced drag. An airfoil is far more complex a shape, but for good cause - the geometry of an airfoil is intended to streamline the wing area upon which the reduced pressure in the fluid is acting. With the reduced pressure comes an increase in the speed of the fluid flow over the top of the wing. Pressure and Velocity are linked linearly, but momentum goes up with the square of velocity. As a result, the mass moving over the top of the wing has greater momentum. Since a wing must have a trailing edge, the fluid cleaved by the wing will eventually rejoin - when it does, the fluid which has been acted upon over the top of the wing will have a greater momentum (coming from the work done which is propelling the wing through the fluid). The fluid flow will have a velocity vector with a downward component. If one were to integrate along the length of the wing and determine the magnitude of the momentum exchange, it would agree with the results of "bernoulli's principle". Bernoulli just helped develop a way to calculate it without having to take direct measurements of the fluid flow at all points along the chord of an airfoil.
  4. According to NASA, every aerodynamics TEXT BOOK I own, and years of personal professional experience in engineering. You're wrong. Kayaks have zero to do with wings or propellers. Propellers and rotors produce thrust the same exact way a wing produces lift. All the equations for calculating propeller forces are derived from the exact same equations used to determine lift. The air moves as a result of the lift created, not vice versa, and is the result of conservation of momentum (3rd law). There is no such thing as a 'paddling' mechanism in real lift. Ever. What you describe is a very old 'newtonian lift' principle that used to be taught to pilots because it simplified the mechanics behind the physics of flight. I learned the same flawed principle when becoming a pilot. Engineering school (and years of work in the field) have taught me just how wrong it is. But please, keep telling people with professional scientific experience how wrong they are.
  5. Air always has a downward velocity vector when leaving the trailing edge of the wing. I've physically stood under plenty of low flying aircraft and the downwash is definitely there. Helicopters *seem* to push more air because it's a constant downwash, not just a single pass of a blade - the downwash is spread out over the distance the aircraft covers. We also covered how propellers and rotors worked in University. Look up the Kutta effect, and even Nasa's explanation: https://www.grc.nasa.gov/www/k-12/airplane/propth.html Suffice to say, KerikBalm is correct.
  6. Try turning on rigid attachment for hinges and robotics. I've found a noticeable difference in their ability to not spaghettify.
  7. Agreed. Arbitration and forced arbitration can be quite different depending on the context. As another noted, arbitration without a lawyer is also unwise, but is more common because many lack an understanding of how the legal systems works (and justifiably so, until you've had experience with it there's no good way to know or learn). Also true based on my limited understanding - however, that won't change how the potential defendant would treat the case, and an already uphill battle becomes a little bit steeper and little bit taller with these kinds of eula changes. Having to make additional arguments to even get the court to hear the case adds time, cost, energy - which is of course what these kinds of clauses are all about. Raising the friction point enough to discourage legal action.
  8. To be fair, arbitration isn't free. You're one-on-one with someone who is usually (but definitely not always) an ex-judge. Someone used to getting paid more per hour than a trial attorney, and who's often got decades of bench experience. Cheap is not a term I'd associate with the process, and unless damages are provable and substantial - the costs are typically shared. Both parties wind up with significant skin in the game. Versus a trial situation where it's possible in some circumstances to obtain council on contingency (meaning they only get paid if you win, but there's still often smaller costs in the meantime). It's a trade-off. Whether it's a good path or not depends very much on the dispute at hand. People get up in arms about it because it's a principle matter. No one likes giving up freedoms for any reason, especially when not given an alternative and the choice is made effectively made for them. Requiring forced arbitration is a good way to kill an arms length deal between two parties, but it's really hard for 'the masses' to negotiate it away when it's part of the entrance fee for employment or use of a good or service (including entertainment). At the same time, there's always potential for damages. Who knows what the long term plans for the game and software includes? It's always possible for companies to get hacked, for credit card or payment information to be leaked, for personal details to be leaked, for bugs to allow unauthorized use or access to computers, etc. It's not hard to imagine a situation where one might have their credit card info used fraudulently due to a data security breach - and then comes the argument for who's responsible. Such a breach would undoubtedly affect large numbers of users - forcing them to arbitrate individually can take significantly longer and result in much lower damage recovery than a class-action suit. Especially if the per-person damages are fairly small (but add up to a lot).
  9. It's worth noting that forced arbitration waives the right to sue, even in a class action. It holds both parties hostage to the arbitration process and a resolution MUST be reached within that process. That said, the point of arbitration if often to reach the same conclusion a trial would but in a more expedient manner. The discovery process for a trial alone can be a burden no one would want to bear. I'm no lawyer, but I've been through arbitration and found it to be a reasonable compromise compared to the more formal requirements of a trial.
  10. Sorting by diameter, or intended diameter, would help with lots of parts, especially tanks. The more unified look/appearance of the many tanks has made it tougher to pick by sight, for sure.
  11. Agreed. Some sort of toggle to the left of the readout would be better than stretching further down into the viewport. Excellent question, also.
  12. You mean the game with a menu that will let you change gravity, fuel consumption, thermal effects, atmospheric effects, drag, and even allow you to teleport into orbit?
  13. I agree so hard with this. Being able to launch from off-world sites is a great workaround to not having a debug menu for console players, AND there's plenty of folks who's version of gameplay wont hurt in the least by this launch site. Those that don't want it in their game can untick that checkbox. Deciding not to play because there's something too 'cheaty' built-in is short-sighted. We already have a cheat menu. I mean, what's more cheaty than that? Heck, I'd love having this site just to test out quick ideas for stuff I plan to send to Mun. Same way I CHEAT by reverting to launch when it turns out my design sucks or I screwed up staging. I really, truly, whole-heartedly hope this makes it to future PC versions.
  14. And as Nertea said, this isn't the place to discuss such things anyway. What they offer is a different vision and intent than Squads, obviously. If aftermarket versions of the engine are what players want, they already have them It wouldn't. The assumption is that there's only one way to build a ball swivel.